Travel trailers and other mobile housings have heretofore been provided with collapsible tops that can be moved between raised and lowered positions. Various lift mechanisms have been installed to raise and lower the top. Such mechanisms have generally included a collapsible standard or jack at each of the four corners of the top and means for simultaneously actuating the jacks. Such prior lift mechanisms are disclosed in U.S. Pat. Nos. 3,674,305, 4,171,843, 5,704,677 and 5,951,096. In each of these prior lift mechanisms, a central actuator is connected to the corner jacks by flexible incompressible springs guided through conduits having one end rigidly fixed to the central actuator and the opposite end rigidly fixed to the frame of the trailer adjacent the jack to be actuated.